It is not only desirable to protect the environment from debris, particulates, contaminants, biologics, bacteria, chemicals and other airborne material which are produced in industrial plants but to provide similar protection in systems which have a fluid flow that are used in hospital anesthesia systems, plumbing and water delivery systems in buildings and municipalities.
Filtration devices in a plumbing system are used for the water delivery system. However, the prior art devices are difficult to install in existing system and once installed are difficult to maintain. Furthermore, they may require security against contamination.
Hospitals utilize a central location for gases used in delivery to patients in their rooms or in the operating rooms. A problem recognized in hospitals is that contaminants such as mold or pathogens are capable of growth in the delivery systems and require frequent inspection and cleaning. Such operation is not efficient and is costly. New Jersey at the present time is the only state which requires maintenance of any gas delivery system. It would be desirable to provide a system which can be easily installed that filters any undesirable matter found in the oxygen or anesthesia or any gas systems.
Water delivery systems should be provided with security means to delivery potable water in the event of accidental or deliberate contamination. This invention relates to a security filter system and/or arrangement that allows more efficient and reliable operation, permits more effective maintenance of the equipment, and also frequently provides installation of the equipment at a significantly lower cost, than have been possible with systems and arrangements previously proposed or used.
One problem with previously proposed multiple unit equipment is that the gas or liquid flow distribution frequently is not uniform either among the units or within the individual units themselves. As a consequence, one unit may be loaded beyond its efficiency while a companion unit receives only a part of its rated load.
Moreover, the arrangement of conduits in known multiple unit equipment is often such that poor gas distribution within the separate units causes uneven loading of the cleaning elements of the units and an accompanying deterioration in cleaning performance. In other words, the cross-sectional flow distribution within a given unit is not uniform, as it should be for optimum efficiency. Although a uniform cross-sectional distribution of the gas within a filter is essential to its efficient operation, it is difficult to achieve because of the relatively low gas velocity (on the order of five feet per second) at which filters are operated and do not secure against a contaminant entering the system.
Because of the threat of terrorists it has become necessary to secure water systems for buildings as well as for cities by installing biological filters which can trap and/or kill pathogens. Moreover, filters can be provided which can signal the presence of pathogens or chemicals by a change in color or other means.